The following is what I reported on the V12 forum when addressing water pump work.
“Took car for test drive today and the out side temperature here is 97+. Temp gauge stayed at the center of the N in both highway and stop and go traffic.
That’s the good news but the bummer is after much work and effort on A/C system only only giving me 70 degrees at the vents. The condenser was flushed but is original. May be plugged up a bit I suspect after 32 years.
Completely flushed system and had pulled -30hg vacuum for three hours. It held the vacuum over night and vacuumed the system for an other hour before trying to charge the system this morning. Would not take the estimated required 997 grams of R134a. Took maybe 600 grams and stopped trying to add more refrigerant due to high low side pressure of 80 PSIG.”
OK since then while trying to add more 134a and the engine running and A/C on, noticed the metal line of the hose entering the fuel cooler from the TXV was iced up.
Is it possible that the fuel cooler is the obstruction others have said exist since it did not allow a full refrigerant charge?
While on the A/C system questions do any of you know where a custom made condenser for our cars can be purchased?
Thanks in advance for your assistance.
When you reached 80 PSIG charging, was that with the system off or on? I ask because you then add “since then, while trying to add more 134a with the engine running and A/C on.”
You mention line entering the fuel cooler from the TXV. Do you mean from the evaporator outlet? Where was it iced up? If between evaporator and fuel cooler, it is unlikely to be the cooler–that would ice up after the cooler, heading for the compressor suction port.
Too much is uncertain. What is the low side pressure with A/C running? Icing of the low side line after the evaporator can indicate that there is insufficient heat exchange in the evaporator–icing from too low a charge for example, but this takes some time to occur. Can/did you measure the high side pressure?
The icing is on the line from the evaporator to the fuel cooler. Think I screwd up and had that high side valve opened when trying to charge. Thinking of taking the car to an shop where they can recover what ever refrigerant I was able to charge the system with. Then let them pull a vacuum and let them charge it.
If it still wont cool this will be forever a winter diver so long as I have it.
If the fuel cooler was the problem, I think it’d be the line OUT of the fuel cooler that would be iced up. But the fact that that line is iced up is evidence that your refrigerant circuit is working fine. Your problem is probably that the control system has the heater on. Try completely obstructing the coolant flow through the heater circuit and see if it cools any better.
Even if that works, it still won’t get that cold because air through the heater core is not cooled. So you’ll have some cooled air mixed with uncooled air, which will be better than cooled air mixed with heated air but still not as chilly as it should be.
I have adapted paralell flow condenser from later 4.0l xjs
Upgrading to later style parallel flow A/C condenser
Since we are on ac…what is best way to clean drain lines